Draft gear



April 23, 1929. I J. R. CARDWELL DRAFT GEAR Filed Dec. 51, 1925 PatentedApr. 23, 1929.

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JAMES R. CARDWELL, OF CHICAGO, ILLINOIS, ASSIGNOR TO "UNION DRAFT GEARCOM- PANY, OF CHICAGO, ILLINOIS, A CORPORATION OF DELAWARE.

. DRAFT GEAR.

, Application filed December 31, 1925. Serial 1510. 78556.

This invention relates to cushioning devices and more particularly todraft gears for railway cars. 7

One of the objects of the invention is the provision of new and improvedmeans for .frictionally and resiliently absorbing shocks and the likeincident. to butting and travel of railway cars.

' Another object of the invention is the provision of new and improvedmeans for limiting the relative movement of the different parts of theshock absorbing elements upon each other during their operation.

,A still further object of the invention is the provision of a new andimproved shock absorbing element that is simple and rugged inconstruction, cheap to manufacture, ef-

that is not likely to become broken or get out of order.

Other and further objects and advantages of the invention will appearfrom the following description taken in connection with the accompanyingdrawings, in which Fig. 1 is a horizontal section of the device shown inposition between the center sills of a railway car, with parts'brokenaway Fig. 2 is a section on line 2-2 of Fig. 1;

Fig. 3 is a section on an enlarged scale of a portion of the shockabsorbing element.

On the drawings, the reference characters 7 10 and 11 designate thecenter sills of a rail- I absorbing element 21 which may be termed waycar which are provided with the draft lugs 12 and 18 and the buffer lugs14 and 15 between which the draft gear 19 is adapted to be inserted inthe usual manner.

A rear follower 17 is adapted to engage the buffer lugs 14 and 15, and afront follower 18 is adapted to engage the draft lugs 12 and 13.

The draft gear 19 is mounted between said followers and comprisesessentially the shock a ring spring. This element is'made up of aplurality of sets of metallic rings22 and 23. I Each of the rings 23 isbeveled on'its periphery from the center inwardly as at 24' and 25 forforming a double cone for telescopically engaging the correspondinglybeveled inner surfaces 26 and 27 respectively on the adjacent rings 22,see Fig. 3.

rings 23 and of the cooperating bevel sur faces'flfi and 27 on the rings22 is less than.

The angle of the beveled surfaces 24, 25 on the the angle of repose forthe metal composing the rings, whereby when they are compressed theywill resume their original position when the compressive force isrelieved.

' The shock absorbing function of the element is due to the elasticityof therings and their frictional contact between the cooperating beveledsurfaces. Due to the great forces to which theyare subjected, there isalways danger that the rings will be expanded or compressed beyond theirlimits of elasticity and thereby become distorted or broken 'unlessmeans be provided for limiting the relative movement of said rings. Inthe form of i.

the device selected to illustrate one embodiment of the invention, stepsor shoulders'are 1 provided on one set of rings for engaging the ficlentin operation, easily assembled, and

other set to limit their telescopic movement. Since the rings that areexpanded are more likely to be distorted than the rings that arecompressed, the outer rings are each shown as being provided with aninternal rib, shoulder or flange 28. These flanges are not only adaptedto engage the ends of the inner rings to limit the telescopic action ofthe rings, but also act as reinforcing ribs for the outer rings. Theprovision of these stops to limit the telescopic movement ofthe rings isconsidered an important featureof this invention. I

In order to obviate too much strain on the flanges or stops 28 the partsare preferably so arranged that the distance between the shoulder 28 andthe ends of the ring 22 is substantially equal to the length of one of lDuring compression of the gear, the-frietional resistance between therings will vary,

but the stops 28 will prevent any abnormal telescopic movement betweenany two rings,

consequently none of the rings will be overstrained during compression.Ifit were not for the stops 28 one of the rings 22 might telescope oneof the rings 23 beyond the center of said ring, as when there is lessfrictional resistance to its movement than the opposed ring 22 andresult inabroken or distorted 7 With the stops none eftbe rings 22 iring need be employed at each end of the gear in order that thecompression and expansion of all the rings shall be uniform throughoutthe gear. In other words, a full ring employed at eachend of the gearwould offer twice the resistance to compression as one oftheintermediaterings since it is acted upon at one endonly by thecompressive force, and consequently the telescopic action instead. ofcon'ipressing the end rings to the Same extent as the intermediate oneswould tend to abnormally expand the adjacent rings 22, which mightresult in rupture or permanent distortlon of said ad acent rings. By

the use of half rings at the ends of the gearv the'gear itself 18somewhat shortened.

Suitable means are provided for holding the rings 22 and 23 in assembledrelation.

As shown, a, plate 29 having a circular depression 31is provided at oneend of the device, and a plate 32 having a central depression 33 isprovided at the other end of the device, The rings are'adapted to engageabout the projections which are preferably circular, for positioningsaid rings. A bolt 34: extends axially through the depressions 29 and 33and is provided with a nut 35 having a flange forming a spring seat 36.A spring 37 is mountedon the bolt 34 between the bottom of thedepression 33. and the spring seat The head 42 of the bolt is housed inthe recess formed by the depressed portion 29 and the spring seat 35, ishoused in the other depression 33. By means of this arrangement thetelescopic rings 22 and 23, are held in assembled relation by the bolt34audspring 37 and the head and nut of the bolt areprotected by thedepressed portions during compression of the gear.

In the operation of the device, any sudden jerks or buffs of thecoupler'head are transmitted through the yoke 41 to the draft gear andcause the metallic rings to telescope each other. The resiliency of therlngs will per- 1111t only a slight telescopic action, between any tworings, but the aggregate-movement is suflicient. The resiliency of therings and the friction. of their engaging surfaces are suflicient toabsorb the shocks incident to the voases which is adapted to engage thedepression 31,.

and the follower 17 is provided with a similar flange 39 for engaglngthe depression 33.

The yoke 41 of the coupler extends about the followers and gear in theusual manner.

- While I have shown the shock absorber ele- .ment 21 as being employedin connection with a draft gear, it is understood that it maybe employedin other relations.

It is thought from the foregoing taken in connection with theaccompanylng drawings, that the construction and operation of my devicewill be apparent to those skilled in the art, and that various changesin size, shape, proportion and details of construct on may be madewithout departing from the spirit and scope of the appended claims.

I claim as my invention: 1. A shock absorbing member comprising aplurality of telescopic closed rings, certain of said rings havinginclined peripheral wedging faces for frictionally engaging 00- at eachside thereof flaringoutwardly,a plurality ofclosed metallic rings havingconeshaped peripheral surfaces for frictionally and telescopicallyengagingsaid openings and projections on one of said members forlimitingthev telescopic movement of the adjacent members.

4:- In combination, a pair of center sills,

draft and bufier lugs on said sills, followers engaging said lugs, shockabsorber mechanism between said followers, a draft yoke about saidmechanism, said mechanism comprising a plurality of telescopicallyarranged inner and outer closed rings, said inner rings being providedwith peripheral wedging faces for frictionally engaging internalfrictionjfaces on said outerrings and pro ections on certain of saidrings for limiting the telescopic movement of said rings.

5.. A shock absorbing element comprising an inner and an outer set ofclosed metallic rings telescopically arranged, and reinforcing ribs onone of said rings for limiting the telescopic movement of said ringsduring the compression of the same.

6. A shock absorbing element for railway draft gears comprising an outerset of closed metallic rings each having an internal conical face ateach side thereof, an inner set of closed metallic rings each having anexternal conical face at each side for telescopically engaging theinternal conical faces of the adjacent outer 5 rings, the angle of saidconical faces being less than the angle of repose and shoulders on oneset of said rings for limiting the in- Ward movement of the other set ofrings.

7. A shock absorbing mechanism for rail- 10 Way draft gears, comprisinga pairof plates having depressed portions, a plurality of telescopicallyarranged closed rings engaging said depressed portions, a bolt extendingthrough said depressed portions, a nut forming a spring seat on theinner end of said bolt and a spring between said seat and one of saiddepressed portions-for holding said rings in assembled relation.

In testimony whereof I afiix my signature. JAMES R. CARDWELL.

